You can own a corporation with about $400 and an hour of filling out a form online, plus a month or so waiting for various government agencies to process it.

The hard part is getting that corp to own anything of value, since it starts with just the money you put in. But this is still a viable path to wealth for people with time horizons measured in years rather than days. (And all the people who want immediate gratification provides a fairly large market to trade with.)